A device described in Japanese Patent Application Publication No. 2004-316831 (JP 2004-316831 A) (Patent Document 1) is already known as a control device that controls such a vehicle drive device as described above. The terms or expressions in Patent Document 1 are cited in parentheses “[ ]” in the description of this section “BACKGROUND ART.” This control device causes the rotating electrical machine [motor-generator 2] to add or absorb torque according to the combination of the direction in which the speed ratio is changed [upshift or downshift] and the operating state of the internal combustion engine [whether the engine power is on or the engine power is off] during shift operation. For example, in order to perform downshift when the engine power is off, the control device increases the rotational speed of an input-side rotating member [transmission input shaft 5] of the speed change mechanism [stepped automatic transmission 3] by increasing torque of the rotating electrical machine which is transferred to the input-side rotating member. Responsive shift control can thus be performed while reducing shift shock.
In the control device of Patent Document 1, however, a primary component that increases the rotational speed of the input-side rotating member for shift assist during the shift control for downshift is limited to the rotating electrical machine. Accordingly, sufficient torque required may not be output depending on the situation where the rotating electrical machine is in. As a result, intended control may not be appropriately performed, and sufficient reduction in shift shock may not be achieved.